使用rvm来安装ruby
step1
| 1 | $ curl -L get.rvm.io | bash -s stable | 
step2
| 1 | $ source ~/.bashrc $ source ~/.bash_profile$ rvm -v | 
step3
| 1 | $ rvm list known | 
step4
| 1 | $ rvm install 2.2.0 | 
如果Step4失败,可以进行如下尝试
| 1 | sudo chown -R $(whoami):admin /usr/local | 
| 1 | $ curl -L get.rvm.io | bash -s stable | 
| 1 | $ source ~/.bashrc $ source ~/.bash_profile$ rvm -v | 
| 1 | $ rvm list known | 
| 1 | $ rvm install 2.2.0 | 
| 1 | sudo chown -R $(whoami):admin /usr/local |